RC Tank Warfare community hobby forum

Indeed. Even the best controllers are limited by what the wiring and other components can withstand without de-soldering itself, or making ‘magic smoke’. ( been there, done that.. big 700-size cobalt motors in large hydroplanes + almost 30v in NiCads. And a too large a prop.. Let’s say the FET’s were allright.. the mainboard connectors and wiring not so much )

We are lucky with the last gen 6.1xx Heng Long controllers, though. Precise control, Voltage cutoff, higher load capacity, Metal casings even. They’ve come a loooong way from the horrendous 27mc offerings of yore. And the included NiCads? Oh, my word, were théy bad.

Bottomline: The currently included LiIons aren’t really bad, but just cannot provide enough power for longer stints. Voltage cutoff will intervene before they are actually drained.
Luckily better batteries are plenty. The only problem being Heng Long’s T90 and T72 with their tiiiny battery compartments. Forcing One to use the smallish LiIons or purchase the (imho) in the UK somewhat expensive Arrowmax 100c/50c AM 700994 packs, or the Admiral LiIon packs for HL tanks.

Jay-Em wrote: We are lucky with the last gen 6.1xx Heng Long controllers, though. Precise control, Voltage cutoff, higher load capacity, Metal casings even. They’ve come a loooong way from the horrendous 27mc offerings of yore.

I have 3 versions of the HL TK 6.x series (6.0, 6.1 and 6.1s), and I have very detailed photos of the TK 7.0 pcb, so maybe someday I will find more time and write something more about them ...

Jay-Em wrote: Bottomline: The currently included LiIons aren’t really bad, but just cannot provide enough power for longer stints. Voltage cutoff will intervene before they are actually drained.
Luckily better batteries are plenty. The only problem being Heng Long’s T90 and T72 with their tiiiny battery compartments. Forcing One to use the smallish LiIons or purchase the (imho) in the UK somewhat expensive Arrowmax 100c/50c AM 700994 packs, or the Admiral LiIon packs for HL tanks.

Yeah. The main feature of the batteries added to the model by the manufacturer is that they must be cheap. Anyone expecting a high-performance battery and a good-quality charger may be disappointed.
First, after the purchase (if the model starts to behave strangely), I would start by replacing the battery. I use the Turnigy 20C 5000mAh Hard Case (for RC cars) and they are fantastic. On a single charge, the 6 kg model drives over rough terrain for over 60-70 minutes. My son needs nothing more

Jay-Em wrote: The only problem being Heng Long’s T90 and T72 with their tiiiny battery compartments. Forcing One to use the smallish LiIons or purchase the (imho) in the UK somewhat expensive Arrowmax 100c/50c AM 700994 packs, or the Admiral LiIon packs for HL tanks.

I gave up on the LiIons for my all-metal running gear T-72 at an early stage. I had removed all the ridiculously large plastic cases which HL uses for its LiIons (why do they do that?) from my HL batteries so that I could have supply of small charged ones ready for the T-72, but then picked up one of the Arrowmax LiPos (cost me €35, which was cheaper than some I saw), so now I get a reasonable run time from one battery. There’s so little space in the T-72 hull with the protruding turret mechanisms as supplied that everything is a tight fit.

I’m learning much about batteries that I didn’t know that I didn’t know from the forum experts here...thanks!

My 4 cell Li-Ion (2S2P) 18650 based battery pack works really well in my T-72 with a long runtime. With a slight mod to the battery compartment, it fit in the stock location also.

abramsky wrote: ↑Mon May 03, 2021 2:53 pm
Mainly because the ESC circuit of the TK 6.1 uses:
MOSFET 80N03
Maximum Drain-Source Voltage 30V
Continuous Drain Current 80A (25 ° C)
Continuous Drain Current 60A (100 ° C)
Drain Current (pulsed) 320A
Total Power Dissipation - 150W ( at TC = 25 ° C )
Maximum Junction Temperature - 175 ° C

I'm still a little confused about these things.
Are those parameters (60A/80A) valid for both motors together, or 80A each motor?

Since 50koruny has reopened this post from 2021, I chime in, too, with a simple question. Timbo68 said he "removed all the ridiculously large plastic cases which HL uses for its LiIons." The TK7.0 boards do wonders for the newer HengLong tanks, but the batteries seem to be hidden in goofy plastic replicas of the NMHI batteries. Before I perform a "batterectomy," I thought I might be cautious and ask, if I can just cut those plastic cases open--of course with due caution so as not to cut wires, etc. Advice?

A gentle squeeze with a vise, slip joint pliers or a light rap with a hammer on the end of the case without the wires (narrow edge, on the seam) will get you started. A screw driver will help with the rest if needed.

Thanks, Eric! Your picture of the opened case tells me everything I needed to know. Now I can go nuts tomorrow opening bulky batteries. Yippee!

50koruny wrote: ↑Tue May 28, 2024 11:03 pm

abramsky wrote: ↑Mon May 03, 2021 2:53 pm
Mainly because the ESC circuit of the TK 6.1 uses:
MOSFET 80N03
Maximum Drain-Source Voltage 30V
Continuous Drain Current 80A (25 ° C)
Continuous Drain Current 60A (100 ° C)
Drain Current (pulsed) 320A
Total Power Dissipation - 150W ( at TC = 25 ° C )
Maximum Junction Temperature - 175 ° C

I'm still a little confused about these things.
Are those parameters (60A/80A) valid for both motors together, or 80A each motor?

Hello after the break. The given parameters refer to the current efficiency of a single MOSFET. So you treat these values ​​for each engine separately. Although I have never managed to block the motor so much that it draws more than 10A - but my son managed to burn one of the 3 windings of one motor - MOSFETs are doing very well for this.
In MFU TK 6.0/6.1 and TK 7.0/7.1 there are a total of 8 MOSFETs, 4 on each side of the PCB (2x left front, 2x right front, 2x left rear and 2x right rear).

Please indulge my sense of humor. Compare the exchange above between abramsky and 50koruny to that between Ecam and me. We function on hilariously different levels here on RCTW. It's fun!